1. Field of the Invention
The present invention relates to a glass run to be attached to a vehicle door.
2. Related Art
Generally, a vehicle door for an automobile or the like is provided with a glass run that seals a peripheral portion of a door glass which slides. The glass run has a substantially U-shaped cross-section main body and a pair of seal lips respectively extending from both side walls of the main body to an inner side thereof. The main body is fit into a mounting portion (e.g., a sash) provided on an inner peripheral side of a door frame. Further, vehicle-interior and vehicle-exterior surfaces of a peripheral edge portion of the door glass are sealed by the pair of seal lips.
Moreover, in a case where a corner portion of a door frame is formed into a right-angled shape or an acute-angled shape like a rear upper corner portion of a front door, and where an associated corner part of a door opening portion of a body is gently curved, there is a fear that a gap is formed between the glass run provided on the corner portion and a weatherstrip provided on the body, and that the quality of the appearance of a vehicle is degraded. Thus, a conventional glass run is constructed so that the aforementioned gap is covered with an extension wall part formed in a corner portion thereof to extend from a vehicle-interior side wall to an inner periphery thereof, and that the quality of the appearance is improved (see, e.g., JP-A-8-295134).
However, there is a fear that the extension wall part follows, e.g., a movement of the seal lip, which is caused by a sliding motion of the door glass, and that an end portion (inner peripheral side edge portion) of the extension wall part is floated up. In order to cope with this problem, a conventional glass run is constructed so that a catching portion is provided in the vicinity of an end portion of the extension wall part, and that the catching portion is caught on an interior member, such as a garnish, thereby preventing the end portion from being floated up (see, e. g., JP-A-2004-50881).
Further, when a glass run is molded, it is necessary that a mold (core) for forming an inner peripheral surface of each of a main body and a pair of seal lips is inserted into a molded portion for forming a corner portion of a glass run. Generally, a glass run is formed into a developed shape, in which both side walls of the main body portion are largely opened, to maintain the holding strength of the core. However, in a case where the main body is deformed so that both side walls thereof are narrowed when the glass run is attached to a sash, the aforementioned extension wall part, more specifically, there is a fear that an inner peripheral side edge portion thereof is deformed so as to undulate. Additionally, even in the case of providing the catching portion, as described in the aforementioned JP-A-2004-50881, it is difficult to prevent the deformation of the extension wall part. In some case, the deformation may cause disengagement of the catching portion from an interior member.
In order to cope with this problem, it is considered to suppress deformation of the extension wall portion by increasing the thickness thereof. However, in a case where the glass run is made by a thermoplastic resin material such as an olefinic thermoplastic elastomer (TPO), it is fear that a sink mark is formed on a vehicle-exterior side surface, i.e., a design surface of the extension wall portion due to characteristics of the material when the glass run is formed.